Wheeled vehicles have been known for centuries and several various types of suspension systems have been adopted to smooth the vehicle ride for occupants. Conventional suspension systems used on automobiles typically include coil springs and/or leaf springs that secure the wheel axles to the vehicle frame or carriage. In these arrangements, the springs support the vehicle frame above the axle to soften the ride. These conventional suspension systems have been refined and are particularly suited for use with vehicles commonly driven over relatively smooth surfaces such as roads and the like. Further, when traveling over smooth surfaces such as roads, vehicles are generally driven at relatively high speeds and they typically require suspension systems that are “tight.” However, such “tight” systems often fail to perform satisfactorily when the vehicle is driven over very rough terrain. As a result, these suspension systems often must be modified for travel over rough terrain. One type of modified vehicle commonly used to traverse rough terrain is often referred to as a four-wheel drive vehicle.
Four-wheel drive vehicles typically employ heavy duty springs and shocks and they also generally supply motive power to both the front and rear wheels. In many other respects, these vehicles are generally very similar to vehicles primarily designed for operation on relatively smooth surfaces. For example, four-wheel drive vehicles often utilize rigid wheel axles or unibody frames that restrict wheel movement in the vertical direction. Such constructions prevent sufficient wheel movement to traverse some obstacles. Also, another vexatious problem experienced with typical four-wheel drive vehicles is that as an individual wheel moves vertically, the remaining wheels lose traction as a result of the spring suspension systems.
To overcome these problems, four-wheel drive vehicles often employ “loose” suspensions that facilitate a wider degree of wheel movement. The aptly named “Monster Trucks” with greatly raised bodies and gigantic tires are examples of such attempts. However, these “loose suspensions” adversely affect the performance of the vehicle when it is driven over normal roads at high speeds. These suspension systems have too much sway or lateral movement and the vehicle bodies tend to “lean” to one side during vehicle movements. This lean can often produce catastrophic results since the vehicle is often plagued by undesirable body sway in curves or during cornering.